Clinical Experience of Bevacizumab for Radiation Necrosis in Patients with Brain Metastasis.

Abstract

BACKGROUND:

As the application of radiotherapy to brain metastasis (BM) increases, the incidence of radiation necrosis (RN) as a late toxicity of radiotherapy also increases. However, no specific treatment for RN is indicated except long-term steroids. Here, we summarize the clinical results of bevacizumab (BEV) for RN.

METHODS:

Ten patients with RN who were treated with BEV monotherapy (7 mg/kg) were retrospectively reviewed. RN diagnosis was made using MRI with or without perfusion MRI. Radiological response was based on Response Assessment in Neuro-Oncology criteria for BM. The initial response was observed after 2 cycles every 2 weeks, and maintenance observed after 3 cycles every 3-6 weeks of increasing length intervals.

RESULTS:

The initial response of gadolinium (Gd) enhancement diameter maintained stable disease (SD) in 9 patients, and 1 patient showed partial response (PR). The initial fluid-attenuated inversion recovery (FLAIR) response showed PR in 4 patients and SD in 6 patients. The best radiological response was observed in 9 patients. Gd enhancement response was 6 PR and 3 SD between 15-43 weeks. Reduction of FLAIR showed PR in 5 patients and SD in 4 patients. Clinical improvement was observed in all but 1 patient. Five patients were maintained on protocol with durable response up to 23 cycles. However, 2 patients stopped treatment due to primary cancer progression, 1 patient received surgical removal from tumor recurrence, and 1 patient changed to systemic chemotherapy for new BM. Grade 3 intractable hypertension occurred in 1 patient who had already received antihypertensive medication.

CONCLUSION:

BEV treatment for RN from BM radiotherapy resulted in favorable radiological (60%) and clinical responses (90%). Side effects were expectable and controllable. We anticipate prospective clinical trials to verify the effect of BEV monotherapy for RN.

• Authors: Moowan Park, Ho Shin Gwak, Sang Hyeon Lee, Young Joo Lee, Ji Woong Kwon, Sang Hoon Shin, Heon Yoo
• Journal: Brain tumor research and treatment (Brain Tumor Res Treat) Vol. 8 Issue 2 Pg. 93-102 (Oct 2020) ISSN: 2288-2405 [Print] Korea (South)
• PMID: 32648383 (Publication Type: Journal Article)
• Copyright: Copyright © 2020 The Korean Brain Tumor Society, The Korean Society for Neuro-Oncology, and The Korean Society for Pediatric Neuro-Oncology.